Medication Summary
Antibiotics are the mainstay of therapy for bacterial vaginosis. Medications include metronidazole (Flagyl), clindamycin (Cleocin) oral or vaginal suppositories, and metronidazole vaginal gel (MetroGel-Vaginal). Metronidazole and clindamycin are the preferred medications used to treat Gardnerella infections. See Medication for specific information on these medications.
In September 2017, the FDA approved the first single-dose oral treatment secnidazole (Solosec, Symbiomix Therapeutics) for women with bacterial vaginosis. [22] Approval was based on two randomized, placebo-controlled studies which evaluated the efficacy of secnidazole in treatment of bacterial vaginosis. Efficacy was assessed by clinical outcomes evaluated 21-30 days following a single dose of secnidazole. A clinical responder was defined as having "normal" vaginal discharge, negative "whiff" test, and clue cells < 20%; additional endpoints included Nugent score cure and therapeutic outcome.
In both trials, a statistically significantly greater percentage of patients experienced clinical response (Trial 1: 67.7%; Trial 2: 53.3%), Nugent score cure (Trial 1: 40.3%; Trial 2: 43.9%), and therapeutic response (Trial 1: 40.3%; Trial 2: 34.6%) at 21-30 days following a single dose of Solosec compared to placebo. [23, 24]
A double-blind, randomized controlled trial by Subtil et al that included 5630 pregnant women with bacterial vaginosis reported that systematic screening and subsequent treatment for bacterial vaginosis in women with low-risk pregnancies showed no evidence of risk reduction of late miscarriage or spontaneous very preterm birth. [25]
Antibiotics
Class Summary
Therapy must be comprehensive and cover all likely pathogens in the context of this clinical setting.
Clindamycin (Cleocin)
Bacteriostatic antibiotic used against gram-positive aerobes and gram-positive and gram-negative anaerobes. Inhibits bacterial growth, possibly by blocking dissociation of peptidyl tRNA from ribosomes, causing RNA-dependent protein synthesis to arrest. Available as capsule and 2% vaginal cream formulation.
Metronidazole (Flagyl)
Bactericidal antibiotic enters bacterial cell and is reduced by electron transport proteins. Free radicals are formed, which react with intracellular components and/or DNA and result in subsequent cell death. Antimicrobial spectrum includes many gram-positive and gram-negative anaerobes and protozoal parasites.
Metronidazole (MetroGel-Vaginal)
Bactericidal antibiotic enters the bacterial cell and is reduced by electron transport proteins. Free radicals are formed, which react with intracellular components and/or DNA and result in subsequent cell death. Antimicrobial spectrum includes many gram-positive and gram-negative anaerobes and protozoal parasites.
Secnidazole (Solosec)
Secnidazole is a nitroimidazole derivative; 5-nitroimidazoles enters the bacterial cell as an inactive prodrug where the nitro group is reduced by bacterial enzymes to radical anions; it is believed that these radical anions interfere with bacterial DNA synthesis of susceptible isolates. It is indicated for bacterial vaginosis in females aged 12 years and older.